This man made Britart what it is. He would have hated it

It's just over nine years since the art critic Peter Fuller was killed in a car crash at the age of 43. Fellow critics and art world luminaries queued up to deliver tributes at the time, but many must have had their fingers crossed: Fuller was widely loathed. But no one doubted that this man, who founded a successful art magazine and wrote a series of provocative books, would be remembered as a great critic.

Yet this fierce defender of figurative painting and enemy of the avant garde has now been almost erased from the history of British art. His legacy has been reduced to the career of his protegee Sister Wendy Beckett and the annual Peter Fuller Lecture, to be given this evening by former Conservative minister George Walden. Even Modern Painters, the magazine he founded in 1987, officially abandoned his editorial policy two years ago to become broadly sympathetic to conceptual art.

Fuller died just as Young British Artists like Gary Hume, Sarah Lucas and Damien Hirst were emerging, in the year Rachel Whiteread cast a room in Archway to form her sculpture Ghost. Fuller should have been here to give young artists someone less predictable to struggle against than Brian Sewell and less coarse than David Lee, who recently suggested in his magazine Art Review that Whiteread should make a cast of the space between her ears.

Fuller would have been a more provocative presence than these critics because he was not a conservative. He started as the Marxist disciple of radical art critic John Berger but became preoccupied with the reality of aesthetic experience. Everything he said had a grit and awkwardness that forced champions of new art to argue with him, however extreme and irritating his criticisms.

Fuller has disappeared from the story of British art because that story has been mythicised and thinned out. The amazing thing about art in late 20th-century Britain is not the success of a few artists but the way a country that has always seen itself as literary rather than visual, and produced some of the world's drabbest painters to prove it, has turned to art as its favourite form of expression.

The popularisation of art in Britain is a massive cultural transformation. It was born in a ferment of contested ideas and passions in which Fuller did as much as anyone to make Britain a visual culture. The intensity of his criticism was part of the same mad climate in which artists were inspired to pickle fish and make casts of rooms. Peter Fuller is an unlikely, unsung godparent of the new British art.

Even at his most dogmatic, Fuller wrote in a peculiar autobiographical fashion that allowed his ideas' construction to show through. This is an ineffective way of writing denunciatory criticism. When the epigrammatic Robert Hughes dismantles an artist, he does so in the voice of authority. Peter Fuller never learned that elegant manner and his writing cries out for a furious reply.

'Peter loved enemies and he was very combative in personal life and professional life,' remembers Karen Wright, who edits his magazine Modern Painters. 'Sometimes he was nasty just for the sake of being nasty.' But he generated debate in a way that dragged art from the margins to the centre of British culture. Given the way he made himself hated in the process it's interesting that one of his favourite paintings was Holman Hunt's The Scapegoat.

Fuller encapsulated the unlikeliness of Britain's love affair with art in his appearance and writing style. The son of a Baptist doctor, he had years of psychoanalysis to overcome his neuroses. With his heavy spectacles, froggy face and clumsy prose, he was not someone you'd peg as an art critic. 'He walked differently to anybody else, he sat differently to anybody else,' recalls his widow Stephanie Burns. When he appeared on BBC2's The Late Show in the late 80s debating with fellow critic Matthew Collings, the contest was one of style as much as of ideas. Collings the ironist battled with Fuller who had no irony about himself.

In his memoir, Marches Past, Fuller recounts earlier feelings of insecurity in the presence of the charismatic John Berger. He was mortified when his car broke down as he drove Berger from an airport, and crippled by self-doubt when the critic looked disapprovingly at his pet goldfish.

Fuller may have been insecure but he compensated for it with criticism of unbridled vitriol. He became famous for denouncing artists - Gilbert and George, Francis Bacon, Richard Long. He accused the gentle and reclusive Long of being a phoney purveyor of fetishistic art. His widow believes he would have hated 90s British art; she says that while he never wrote about Damien Hirst, Fuller thought his work 'fatuous'.

Other friends are not so sure. 'It would be impossible to predict what Peter would have thought about art now,' says Roy Oxlade, who runs the Peter Fuller Memorial Foundation, which organises the annual speech. 'I expect it would have been a surprise to those who want to put him in a particular bracket.' British art changed convulsively and absolutely at the end of the 80s. There's no lineage from British conceptual artists of the 80s to the Hirst generation; instead, there's a sense of history and habit being jettisoned in a cataclysmic event. Fuller played a part by creating an atmosphere of febrile populism around British art.

What's the purpose of art criticism anyway? The success of young British artists in the 90s has made that question urgent. These artists were not discovered by critics but grudgingly accepted long after they became familiar names. Like Warhol in the 60s or Hogarth in the 18th century, Hirst escaped the critical discourses of the art world by appealing to a wider audience. Fuller wanted to do the same thing as a critic. He didn't write within any established language of art criticism. He was neither a newspaper columnist nor an academic theorist but something else - something weird and unhinged.

The best thing about Fuller's writing is its autodidacticism. This is what connects it with 90s British art. In the 90s, artists have used whatever tools have come to hand to make powerful art without worrying about art-historical conventions; their work can be seen as a democratic rejection of a culture in which knowledge about art was for centuries the preserve of the aristocracy. Fuller was just as much an outsider to the polite conventions of English criticism.

The amazing thing is how he managed to be such an autodidact despite his impeccable education at Epsom College and Peterhouse, Cambridge. He peppered his writing with ideas in a very un-British way (quoting Marx, Freud and child psychologist DW Winnicot), with the appetite of a studious 15-year-old. Because of his thirst for knowledge (without the elitist language of art theory), his writing is singularly open in its fumbling for conclusions, which are implausibly presented as God-given truths.

Art for him was an obsession, as he wrote in his book Art And Psychoanalysis, in which he relates the pleasure of art to the child's first relationships with objects and suggests that 'beauty' lies in a utopian sense of reconciliation with the maternal. In his memoir he relates dreams in which art haunts and torments him.

This emotional immersion in art was the reason he fell out with John Berger, who argued in his 70s TV series Ways Of Seeing that the western oil painting is in the end just a celebration of the commodity. Fuller wrote a book rebutting Berger on the grounds that looking at art is an aesthetic experience, not just an ideological one. Berger stopped talking to him after a bitter phone argument about the Pre-Raphaelites.

Even Fuller's keenest fans would not claim that he was right about everything, or perhaps anything. 'To be frank, some of the artists he admired have faded rapidly into oblivion,' says George Walden. 'I'm a little suspicious of some of his Little England tendencies, too.' But art criticism isn't something you have to agree with. Today, critics are happy to see their writing as contingent, as hesitant. Peter Fuller, proud dogmatist that he was, would shudder at that, but his art criticism in its very extremism reads like an admirably open text. The time when Fuller dominated British art writing was the moment when British art exploded into the excitement of the early 90s, which is gradually ebbing as the new art is institutionalised. Perhaps the art world needs a few more stroppy bastards.

Nasty for the sake of it?

Some of Peter Fuller's typically outspoken judgments:

On American artist Jasper Johns'I feel that his painting involved no attempt to depict imaginatively his experience; nor do his images convey any convincing grasp over objects or the world. In what other area of human life could such feeble ideas be so over-priced?'

On America'The stench of the art world in America is even stronger than in England. Every picture is packaged with the Clingfilm of cash.'

On art and Thatcherism'Mrs Thatcher initiated a regime of stunning philistinism and destructiveness, which aimed to sweep away the last vestige in public art policy of exactly those things to which the Marxists had objected. If the point is not to understand the world but to change it, the palm must be awarded to Mrs Thatcher. She "deconstructed" traditional aesthetic values much more effectively than a thousand polytechnic Marxists and art-school deconstructionists.'

On Britart'The philistine complicity of left and right is a fact of life for Britain's art institutions. Charles Saatchi, the advertising man who did so much to bring Mrs Thatcher to power, has amassed a large collection of anaesthetic art, praised by many of the trendiest left theorists of recent years.'

On Francis Bacon'An artist of persuasive power and undeniable ability, but he used his expressive skills to denigrate and degrade.'

On Andy Warhol'If he had been born in 17th-century Holland, when Vermeer was watching the way that light modulated itself over the walls, Andy Warhol would have been trying to use a camera obscura to photograph himself in the mirror.'

On Gilbert and George'Praised by the left's critics for their hatred of unique objects and "elitist" aesthetic ideas, they are vociferous supporters of Mrs Thatcher.'

 The Peter Fuller Lecture is at the lecture theatre of the University of London's Darwin Building in Gower Street, London WC1, at 6pm tonight. Admission free.